Potentiometers used in circuit bending allow for manipulation of the sounds coming out of the circuits. In this case the pots are connected to the microcontroller instead of the sound generation circuitry which means you can do whatever you want with them depending on how creative you are with the code. So far he’s just starting to get the new set of interfaces to play nicely over the serial connection. This could end up being quite popular as it only requires the addition of a multiplexer IC, the potentiometers, and the knobs.

Bliptronic 5000 at Thinkgeek.com
$50.00 and worth it for parts alone.
I have been having fun with it since xmas but am cracking it open today and see about some mods.
It is “affordable to ruin” since the wife has another one on the way hehe.
Give it a peek. not trying to spam.
Might help with ideas or be a shortcut.http://www.thinkgeek.com/electronics/musical-instruments/c4e1/
I’m already thinking of at least clocking to MIDI since its bpm selection leaves a lil something to be desired. Bends look pretty easy but not super spectacular. But… daughterboards are always a nice thing heh.

Capacitor in series with chip power supply, wont work. Chip is probably powered via it’s ESD protection diodes from an input being high. The cap should go OVER the power supply pins, eg from VCC to GND